wicks



Nov. 27, 1923. 1,475,612

J. WICKS MEASURED SERVICE TELEPHONE SYSTEM Filed Dec. 13 1919 2Sheets-Sheet 1 Hllll [z'zuEnZ/Jr Juhn Ill mks Nov. 27, 1923.

1,475,612 J. wlcKs MEASURED SERVICE TELEPHONE SYSTEM Filed Dec. 13, 19192 Sheets-$heet 2 [nusnlur Jul-m Inficks H Ty:

Patented Nov. 27, 1923.

UNITEI) STATES PATENT OFFICE.

JOHN WICKS, CHICAGO, ILLINOIS, ASSIGNOR TO AUTOMATIC ELECTRIC COMPANY,OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

MEASURED-SERVICE TELEPHONE SYSTEIJI.

Application filed December 13. 1919.

T0 aZZ whom it may concern Be itknown that I, JoHN VICKS, a citizen ofthe United States of America, and a resident of Chicago, Cook County.and State of Illinois, have invented certain new and useful Improvementsin liIeasured-Service Telephone Systems, of which the following is aspecification.

My invention relates in general to meas ured service telephone systemsbut more particularly to methods of providing measured service inautomatic telephone systems; and the principal object is the provision.in an automatic system comprising well known types of pay stations andmeans for controlling the same automatically to collect and refunddeposited coins, of means whereby the paystations may be controlled byoperators in special cases, as where a subscriber calls a long distanceoperator and is connected div rectly with another subscriber in adistant exchange, this type of connection being commonly referred to astwo number call.

Further objects consist in the provision of substation meters forregistering calls. which are adapted to be operated by the samemechanism and in the same circuni stances as is the coin collecting orpay station apparatus above referred to; and in the provision of variousimprovements in ci1= cuits, all of which will be described in thefollowing specification, reference being had. to the accompanyingdrawings forming a part thereof.

Referring to the drawings comprising Figs. 1 and 2, the general layoutof the systcm therein disclosed may be described as follows: The twosubstations A and A" shown in Fig. 1 are automatic substations which,except for the associated i'ncasured service equipment, are of the usualtype and are each provided with talking apparatus and an automaticcalling device or impulse sender. Substation A is provided, in addition,with a well known type of coin collecting apparatus such as is in wideuse by the so called Bell Telephone Company throughout the UnitedStates. Substation A is provided with a meter for registering callswhich is controllable by the same agencies which control the coincollecting}; equipment at substation A, but which nevertheless is SerialNo. 344,882.

believed to have certain features of novelty which will be pointed out.As shown in the drawing, both substations are connected in bridge ofline conductors 21 and 22. Of course, each substation may have its ownindividual line, and it is to be understood that the invention is notprimarily a party line system; but inasmuch as the substation equipmentis adapted for use on party lines if desired, the two substations havebeen so shown for convenience.

The line conductors 21 and E22 terminate at the exchange in theindividual line switch or trunk selector C, which is of the. well knownrotary type where the wipers always remain onthe contacts last used, andwhose function is to extend the line when calling via an idle trunk lineto a first selector switch. One of the trunl: lines to which the lineswitch C has access is shown extending to the first selector E, 2. Therelay equipment in Fig. 1, which is indicated by reference character D,is a repeater, there being one such repeater inserted in each firstselector trunk.

The first selectors are the first in the series of numerical switches,which may com rise first selectors, second selectors, and connectors,which are used to complete connections between calling and called lines.Reference characters F and I indicate. respectively, a second selectorand a connector. [inch switches are well understood and on this accountit has not been thought necessary to show the complete circuits.

It is customary in automatic exchanges to set aside a certain level ofthe first selectors for calling the long distance operators, the tenthlevel being generally reserved for this purpose. Thus the selector E inFig. 2, has access through its lower levels to groups of trunksextending to second selectors, one of which is the selector F, and hasaccess through its upper or tenth level to a group of trunks extendingto the long distance switch-board. One of these latter trunks is shownin the upper half of Fig. 2 as terminating in the manual equipment 6which comprises a group of relays and a set of lamps, keys, and a ackmultipled at two 0pcrators positions. Each position is supposed to beequipped with cord circuits (not shown) whereby connections can be madewith the long distance lines.

In accordance with the best practice long distance connections torelatively near points where direct toll lines are available areestablished directly by the operator who receives the call, and thecalling subscriber does not have to hang up his receiver and wait to becalled back. These are the so called two number calls so denominatedbecause on the single ticket, which is made out by the operator at theoriginating end, the only data customarily noted down is the number ofthe calling subscriber and the number of the called subscriber. In thecase of fiat rate subscribers the tickets may be collected monthly, butin the case of measured service subscribers the charges must be assessedor collected at once, and the 1' i 1 l 1 recording operators thereroiemust be p10- vided with means whereby they can control the subscribersmeters or coin collecting apparatus. My invention provides such means,the operation of which will now be described.

Before proceeding with the explanation, reference is made to thefollowing patents, which indicate the state of the art, and which arerelied onto supplement the disclosure in the drawings:

U. S. patent to Keith, N0.1,279,352.

U. S. patent to Forsberg, No. 1,043,219.

U. S. patent to Lamb, No..1,193,160.

U. S. patent Keith, Erickson and Erickson, 815,321.

U. S. patent Keith, Erickson and Erickson, 815,176.

U. S. patentto Powell, No. 1,303,553.

In order to explain the control of the meter at substation A" by therepeater D the operation of the circuits in the establishment of a localconnection will first be explained. For this purpose it will be assumedthat the subscriber at substation desired to obtain connection with thesubscriber at substation A When the receiver is removed at substation Aa circuit is completed for the line relay 23 of the line switch C asfollows: ground at G resting contact of armature 28 and the said armmlure, line conductor 22, transmitter T, receiver R, impulse springs ocallingdevice make contact of the switch hook H and he said switch hook.line conductor 21, armature 26 and its resting contact, ttlldtl'l!)winding of the line. relay 23 to battery. The line relay is energizedover the above circuit andupon attracting its armature completes acircuit which extends through the windings of the switching relay 2&-and the stepping magnet in series to battery at the tone busbar 31. Atthe same time relay 23 connects the test wiper 36 to the above circuitat a point midway between the switching relay and the stepping magnet.

' is removed the energization of the lire The operation now depends uponwh t. the trunk line with which the wipers oi line switch C areassociated is or If the trunk line busy the with which the test wiperment will be grounded and as a switchmg relay 24.- will be Sll(l'ifi=l(i ed were standing as shown in the drawiir-L in connection withthe trunlc line enter 11g to the first selector and we in assumefurthermore that this trunk line was idle. Under these circumstanceswhen the rece Irv-1*:

23 is followed immediately by the cmtion of the switching relay 2a,which is of su'iiiciently high resistance to prevent the energization ofthe stepping magnet; and as a result of its 'zation the switching relaydisconnects the line conductors 21 and 22 from the windarmature contactscontrolled by the relay 531 of the repeater D to the windings (i:

coil (32,

relay 53 and the impedance respectively.

Following the extension of the above described by the operation. oswitch (l, the line relay 53 of the i fiidBlll'Ql energized over theline circu and at its armature 69 completes a circuit the slow actingrelay 5d. Upon attra ture 72, relay :34: completes a slow acting relaywhich upon one completes a holding circuit for the switch i relay 24 ofline switch C as follows: at J working contact of mature the saidarmature, winding 7) of the tion coil, conductor 91., test wiperarniature 27 and its working contact, wind the switching relay 24, andthe winding of the stepping magnet 25 to battery.

It is understood that the above holding circuit is established beforethe slow acting line relay 23 has had time to dcenergiae. The operationof armature 74; of relay 55 also closes a circuit for the polarizingwindings of the electro-polarizcd relays .59 and but the polarizingwindings are of high resistance and few turns, and the said relaystherefore are not operated at this time.

.Vhen the line relay of the repeater was energized it closed at itsarmature a circuit for the line relay 101 of the first selector E whichmay be traced as follows: ground at G, lower winding of the line relay101, resting contact of armature 113 and the aid armature, trunkconductor 95, working contact of armature and the sad armature, winding8 of the induction coil, winding of relay 57, winding of relay 58, lowerwinding of relay 59, armature 80 and its resting contact, restingcontact of armature and the said armature, trunk conductor 93, armature112 and its res ing contact, and the upper winding of line relay 101 tobattery. Upon energizing, the line relay completes a circuit for theslow acting release relay 102 in the usual manner, which upon energizingin turn, connects ground to the release trunk conductor 94, at its upperarmature, and at its lower armature prepares a circuit for the verticalmagnet 106. The apparatus at the central otlice is now ready for thereception ofthe plurality of series of impulses which the callingsubscriber at substation A now proceedsto generate through the medium ofthe calling device S in order to complete the desired connection. Beforeconsidering the operat on of the selector in response to the firstseries of impulses the operation which takes place at the substation Awill be briefly explained. When the calling device dial is rotated inaccordance with the first digit, soon as it leaves its normal positionthe shunt springs 6 are closed, with the result that the transmitter Tand the receiver R are short-circuited as usual, and with the additionalresult'that a circuit is completed for the relay 2 as follows: ground atC"- winding of the said relay 2, lower set of contact springs controlledby the said relay, switch hook contact springs 5, middle and upper shuntsprings, impulse springs, and make contact of the switch hook H and thesaid switch hook to the line conductor 21, whence it extends to theexchange and by way of the upper conductor of the line circuit thru thewinding of the line relay 53 of the repeater D to battery Uponenergizing, relay 2 locks itself mechanically and breaks its owncircuit. By the closure of it upper set of contacts, relay 2 alsocompletes a connection from the line conductor .22 thru the windings ofthe polarized relay s1 and the operating magnet 01 the meter M toground. Thus the meter is put in condition to be operated subsequentlyto register the call. It should be stated that the circuit thru thepolarized relay 4 and the meter magnet is of very high resistance anddoes not afi'ect the transmission of impulses, or the talking qualitiesof the circuit.

Returning now to the consideration of the operation of the centraloffice equ pment, when the calling device is operated in ac rcrdancewith the first digit of the number series of interruptions is producedin the l ne c rcuit, thereby producing a series of deenergizations ofthe line relay 53. At its armature 69 and resting contact thercoi theline relay closes a circuit each time it decnergizes tor the slo Yacting relay which relay -s energized the first time its circuit isclosed and remains energized while relay is operating responsive to theinterruptions in the line circuit. In its energized position relay 56connects ground G to the lower line conductor, thereby short circuitingthe impedance coil 62; and also connects the trunk conductors 9? and 95over a direct path which includes only the armature 75 and its workingcontact and the armature 70 of the line relay 53 and its workingcontact. By this means all unnecessary resistance and impedance isremoved from the circuits over which impulses are transmitted to operatethe se lcctor E, and the other switches to be used in establishing theconnection.

lici-iponsive to the interruptions produced in its circuit by theintermittent retractions ot armature 70 ot' the line relay 53, the linerelay 101 of tho first selector E is intermittently dcenergized aplurality of times and at each dcenergization sends an impulse thru thevertical magnet 106 to battery. The slow acting relay 103 which is inseries with the vertical magnet is energized by the first impulse andretains its armature attracted while the vertical magnet is beingoperated. At the first upward movement of the shaft a circuit iscompleted from the grounded release conductor 94 thru the make contactof relay 103 and thru the now closed oil normal contacts 108 to the ste'ng relay l.0-l, which upon energizing, closes a locking circuit foritself at its upper pair of contacts. At the end of the verticaloperation of the switch the slow acting relay 10 5 is dcenergized,thereby closing a circuit tor the rotary magnet 10?), this circuit beingreadily traceable by way oi the lower set of contacts controlled by thestepping relay 104-. which is now energized. Upon energizing, the rotarymagnet operates to advance the wipers 120-122. inclusive, intoengagement with the first set of bank contacts in the level oppositewhich they were raised in the vertical movement of the switch, and alsobreaks the locking circuit of the stepping relay 10st. Relay 10 1therefore dccnergizes and breaks the circuit of the rotary magnet, whichaccordingly reli'nwifi its armature and again closes the in erruptercontact controlled thereby. The ope: ion now depends upon whether thetest wiper 121 is in engagement with a busy test contact or not. t thetest. contact with \vhirh the wiper 121 has made connection is busy itwill be grounded and the stepping relay will again be energized over acircuit including contacts controlled by the switching relay 100. theinterrupter contact controlled by the rotary magnet 105, and the Tiecuergization cppiiig l results in another closure of the circuit oi therotary magnet, which advances the wipers into engageme: 5 with the nextset of bank contacts. This :eration by which the stepping relay ill-l lthe rotary magnet 105 are alternately ined and deenergized takes placevery udly, and will continue until the tcs; "\Hper 121 arrives at anon-busy and grounded test contact. llissuining that i wipers of theswitch were raised opposite to the level in which the terminals oi theline extending to the second selector located, and assuming also thatthis inc is the first idle trunk line in the 1 ion when the test wiper12; arrives test contact 12% it will find no ground iotential and thestepping relay 104 will )t again be energized. Instead, the switchrelayd which was connected in series filth the stepping relay 10 i at thefirst upr. ard movement of the shaft and which until now has remainedshortcircuLed will energize with the result that the trunk conductors 98and. 95 are disconuec'tet from the windings of the line relay 10}. andare extended by way of armaturcs 112 and 113 and wipers 120 and 122 tothe line relay (not shown) of the second selector F. The line andrelease relays of the second selector are accordingly energized over theline in the usual manner and the latter relay closes the usual holdingcircuit which extends by way of release trunk conductor 12?, testcontact 124-, test wiper 121, armature 119 and its working contact,winding ot' the switchins: relay 100, interrupter contact of the rotarymagnet, oil normal springs 108, and the winding of stepping relay 10 ito baty The latter relay remains inoperative because of the highresistance of the switchin relay. 'It will be observed that the releasetrunk conductor 9 1 which is grounded at the repeater D, also suppliesground to the holding circuit just described. This is o't no particularimportance in the present case but is essential in case the selector Eis used to call the long; distance switch board, the trunks to which arenot provided with release trunk conductors,

The sul'iscriher at substation will now operate his calling device inace lance with the remaining digits in the called number. Responsive tointerruptions produced in the line circuit, and repeated by therepeater-D, the second selector F and the connector I are successivelyoperated and the connection thereby completed to the cal.

\runk ed substation A". The operation of these switches is well knownand has been eescribed in the publications previously reterred to andhence will not now be explained in detail. Upon the completion of theconnection suitable ringing apparatus is automatically operated to intacts signal the subscribe at substation 1X hen the receiver is removedfrom the hook a circuit is completed for the back bridge relay 150 ofthe connector I and ti is rela upon energizing reverses the direction orcurrent flow in the incoming trunk line in the usual and well knownmanner. Theeitect of this reversal of current at the repeater D will nowbe consicered. It has been pre iously explained that the bridge acrossthe trunk conductors 93 and 95 includes the relays 5T, 58, and the lowerwinding of clectropolarized relay 59. The usual flow oi? current thruthe bridge from the line relay ot' the switch ahead is su'liicient toenergize relay 5? but not relay which latter relay is or low resistancend also marp'inally adjusted. Also until t 1e c grant is *ersed in thetrunk line by the response of the called subscriber. the windings of theelectropolarized relay 59 are in opposition and this relay remainsinoperative. lVhe toe current is reversed however the two windingsassist each other and relay 59 is operated to close a circuit for theslow acting relay 52 as follows: ground at G, working con tact ofarmature 83 and the said armature, armature 81 and its resting contact,armature 64: and its resting contact and the winding of relay 52 tobattery. Upon energizing, relay 52 establishes a locking circuit foritself at its armature 68, and at its armature 67 prepares a circuitover which. the h voltage battery B may be connec id to trunk conductor92.

l Vhen the conversation is finished both subscribers will replace theirreceiver ll hen the receiver is hung; up at substation A the energizingcircuit of the line relay of the repeater D is permanently opened and tlc said line relay is deenergized to open the circuit of the slow actingrelay and the bridge across the trunk conductors 93 and 95. As a resultof the latter operation the selector and connector switches sed in theestablishment of the connection are released in the usual and wellundcrs-stood manner. The breaking of the circuit of the slow actingrelay 54 is followed by the dcenergization of this relay which thereuponbreaks the circuit of the slow acting: rel y 55 at its armature 72, andat the estin rcoir tact of the same armature closes a circui t tor therelay 51 as follows: ground at armsture 72 and its resting contact;armature it and its working contact (relay 56 was enerp ized by theretraction of armature the. line relay), and the winding of the slowacting; relay 51 to battery.

The above described circuit is closed only for a short interval, for thecircuit of relay 55 has already been broken and when this relaydeenergizes it breaks the circuit of relay 56 which in turn willdeenerg'ize to break the circuit of the slow acting relay 51. WVhile itis energized relay 51 connects ground to conductor 91 by means of itsarmature thereby preventing the line switch C from releasing; and at itsarmature (it connects the lower trunk conductor 92 by way oi the workingcontact of the said armature, armature '67 and its working contact. andthe lamp L to the positive pole of the. high voltage battery B Currentfrom battery l3 will now flow for a brief interval over the trunkconductor 92, line conductor 22. thru the contact springs controlled byrelay 2 at the substation A, thru the winding of the polarized relay i,and thru the winding of the meter magnet to ground. The direction of thecurrent flow as above described is such that the polarized relay 4; isnot operated, but the meter magnet is energized and attracts itsarmature to register a call. At the same time the meter magnet alsocloses its contact springs 7, whereby the line conductor 22 is connectedover another path by Way of the lower winding of relay 3 to ground.Relay 3 is accordingly energized in parallel with the meter magnet andupon attracting its armature releases or unlocks the armature of relay2, with the result that the circuit thru the polarized relay i and themeter magnet is broken. The substation A is now in its originalcondition as it was before the call was initiated. except that the meterM has been operated to register the call. At the repeater D all relayshave been deenergized except relays 51 and the latter relay being lockedto the grounded conductor 91 which is maintained grounded at armature 65of relay 51. When relay 51 deenergizes, therefore, following thebreaking of its circuit by the deenergization of relay 56, relay 52 willbe deenergized also and the repeater will be in its normal condition.

Having described the operation in the case where the called man answershis telephone, I will now describe how the meter is prevented fromregistering and at the same time is disconnected from the line when thereceiver is replaced at substation A after an unsuccessful connection.It will be assumed that the connection has been extended as before thruthe medium of the repeater D, first selector E, second selector F, andthe connector I to the line of substation A and it will be assumedfurther that no response was secured and that finally the receiver wasreplaced at substation A. In this case, since the called subscriber didnot answer, the electro-polarized relay 59 and the slow acting relay 52will not be energized, and when the slow acting relay 51 is operatedfollowing the replacement of the receiver. the high voltage battery 13instead of battery B will beconnected tothe trunk conductor 92 asfollows: battery B lamp L resting contact of armature 79 and the saidarmature, resting contact of armature 67' and the said armature, and theworking contact of armature 66 and the said armature to conductor 92.Current from battery B will now flow over the line conductor 22 and thruthe polarized relay t and the magnet of meter M to ground as before,except that now the flow of current is in the opposite direction and thepolarized relay 4 will be operated. It is well known that a polarizedrelay is extremely sensitive and will operate faster than a magnethaving a heavy armature such as the magnet ot' the meter M. Thepolarized relay 4 therefore operates slightly before the meter magnetand at its left hand pair of contacts short-circuits the latter toprevent its energization, while at its right hand pair of contacts theline conductor 22 is connected thru the lower winding of relay 3 toground. Relay 3 is therefore operated as before to open the circuit thruthe polarized relay 4 and the meter magnet, whereupon the substationwill have been restored to normal condition. The meter M has not beenoperated in this case to register a call, and should not have been, forthe con nection was unsuccessful.

I will now describe briefly the process of obtaining a so called twonumber connection in order to explain how the meter at substation A iscontrolled by an operator. It will be assumed that the subscriber at subtation A desires to obtain connection with a subscriber at somedistantpoint connections to which are obtainable only with theassistance of a recording toll operator. It will be necessary then forthe calling sub scriber to first establish connection with the operatorby calling the digit 0 on his dial, after which the operator will extendthe con nection to the desired line in any suitable manner. Assumingthat the receiver has been removed at substation A and that theconnection has been extended to the first selector E, when the callingdevice is operated in accordance with the digit 0 the selector switch isoperated in the usual manner to raise its shaft step by step until thewipers 120-122, inclusive, stand opposite the tenth level of bankcontacts. Thereafter the trunk selecting movement is initiatedautomatical- 1y as previously described and the wipers are rotated insearch of an idle trunk line. Assuming that the trunk line shown in thedrawing is the first trunk line found to be idle the wipers will bestopped in connection therewith, the private contacts of the 0 levelbeing multipled with all corresponding 0 level trunks and of course arenot grounded unless other selectors are occupying them, and the momentthat an idle or ungrounded contact is reached the shunt circuit aroundrelay 100 is removed, and the switching relay 100 will energize toextend the trunk conductors 93 and 95 by way of wipers 120 and 122 andconductors 140 and 141 to the upper and lower windings of the doublewound line relay 203. respectively. There being no release trunkconductor extendingback from the operators position, the switching relay100 is n'laintained energized by the grounded conductor coming from therepeater D. Upon the extension of the line to relay 203 the said relayis energized and completes a circuit thru the lamp L which is lighted tonotify the operator that a call has been received. l l hen the operatornotices the signal she will insert the answering plug or" one of t 1ecord circuits with which she is provided in the ja ck the same timethrowing her listening key. Operators cord circuits and associatedequip-- ment are well known in the art and hence have not been shown, asany suitable type of such equipment may used. When the plug is insertedin the jack. relay 205 is energized by ground over the sleeve of thecord circuit to open the circuit of the lamp L and also to break thecircuit thru the upper winding of the line relay The result of thisoperation is tov the operator a distinctive audible signal indicatingthat the calling line is a measured: service line, which is produced inthe following manner. Reverting to the repeater D it will be recollectedthat the bridge across the trunk conductors 93 and 95 includes thesecondary winding 8 of the induction coil (unless short-circuited byrelay 57). and the windings of relays 57, 58, and 59 in series. Undernormal conditions current flow thru the bridge is such that only relay5'? is energized, this relay having the function of short circuiting thesecondary winding 5 of the induction coil. Now when the circuit of theline relay 203- at the operators position is broken current tlow in thebridge will be interrupted entirely and relay 57 will be deenergized,thereb including the secondary winding in the circuit. It will beobserved that a circuit normally exists throughout the duration of theconnection whi h extends trom ground G thru the primary winding P ot theinduction coil and by way of trunk conductor 91. wiper 36. winding ofswitching relay 24, winding of stepping magnet hus-har 31, and the lowresistance secondary winding of the signaling machine to battery. Itfollows that a high frequency tone induced in the secondary winding .9which gives the operator an auaible signal. This indicates to her thatthe calling line is a n'ieasured service line. and it may be stated thatall such lines have their stepping magnets, such as magnet 25, of theirassociated line switches connected to battcr at the tone husbar 31instead of direct. It is necessary tor the operator to lmor-r when ameasured service line is calling in order that she may operate thesubstation meter, or collect deposited coins in the case of a paystation, at the proper time.

Having perceived the audible signal, the operator will depress the tonecut-oil key momentarily thereby closing a circuit for the relay 204.Upon energizing, relay 204i locks itself at its armature 208, and atitsarmature 209 reestablishes the circuit extending from the lineconductor 140 thru the upper winding of relay 203 to battery. As aresult relay 203 and the relay 5'? at the repeater D are againenergized, the latter relay short circuiting the secondary windings tocut the tone off the line. The operator will now obtain the desirednumber from the calling subscriber and will proceed to complete theconnection. Before permitting the subscribers to talk however, the meterat substation A must be actuated the proper number of times to pay forthe call and the operator will therefore actuate the key marked Collectaccordingly. Each time the key is actuated a circuit is closed for therelay 202, which upon energizing substitutes the lamp L and high voltagebattery B for the upper winding of the line relay 203 and the regularexchange battery. Although direction of current flow is not changed bythe above operation, it is greatly increased due to the high voltage ofbattery B, with the result that the marginal relay 58 at the repeater Dis energized. The operation ofrelay 58 results in the removal of theshort circuit from the lower winding of electropolarized relay 60 and inthe closure of the circuit of the slow acting relay 51. The lowerwinding of the electro-polarized relay 60 is now included in the bridgeacross the trunk conductors 93 and 95 and the direction of current flowis such that this relay is operated. Upon the operation of relay 51 acircuit is completed which extends from ground by way of the workingcontact of armature 71 and the said armature, armature 63 and itsworking contact and the winding of the line relay 53 to battery. Theline relay 53 is thus maintained energized locally after it isdisconnected from the trunk conductor 90 to prevent the release of theconnection. Relay 51 also connects the battery B to the line conductor92 as follows: battery B lamp L lower winding of relay 61, workingcontact of armature 8a and the said armature, resting contact ofarmature 67 and the said armature, and the working contact of armature66 and the said armature to conduct-or 92. Curs rent from battery B nowflows over the line conductor 22 to substation A and operates the meterM as before to register a call. The meter is not disconnected from theline however, due to a circuit which is completed to the upper windingof the relay 3 as follows: line conductor 22, transmitter T, re

cciv hf. innmlse prings oi the calling dec 5 make contact ol the switchhook H and the said switch hook. contact springs 8, and fl c upperwinding; of relay 3 to ground. The above cir uit is closed at the sametime that the circuit is closed thruthe lowerwinding of relay 3- andsince this relay is differentially wound it not energized and the.armature at relay 2 is not unlocked. It follows that the meter andpolarized relay 4: remain connected to the line and the meter will beactuated as man times as the operator actuates her collect key. It willbe noticed that the circuit over which the meis operated includes thelower winding relay 61 and in case the circuit is cometc at thesubstation the relay 61 will enc 'ize each time that the battery 13 isconnccted to the line at the repeater. As a result the conductor 95 isgrounded. thereby short circnitinn' the lower winding of the line relay203 at the opcrato1"s position. The line relay is accordingly deenerzized and closes a circuit for the lamp L the illumination or whichindicates to the operator that the meter at the calling substation isbeing operated. because it for any reason the meter has not beenconnected to the line the c rcuit to ground at the substation would becpenv relay 61 would not energize. the line relay 203 would not 'i" allback. and the lamp would not be lic'l d. Although as stated this lampindicznes to the operator that the meter is being operated correctly. orrather is properly connected to the line for operation, its chic'l useis to ndicate to the operator. when the callingline is a pay stationline. that the calling subscriber has deposited a coin. Further mentionof this will be ma dc hereinafter.

Having mace, the proper charge for the call as above described. theoperator will per uit the conversation to proceed. When the subscribershave finished they will repla e their receivers and a suitable means ofsupervision in the operators cord is controlled in the proper manner togive the operator a disconnect signal and she will theretore pull downthe connection. mien the receiver is replaced at substation A the linerelay 53 ot the repeater D is deenergized and as a result the selectoris restored to normal and relays 541- and oi the repeater are deener cizcd. As before explained the deenerc-ization of these two relays bringsabout a temporary energization of the relay 51 oi the repeater whichoperates to connect the battery B to the conductor 92 for a hrieiinterval. thereby bringing about the disconnection of the polarizedrelay 4 and the meter trom the l ne before explained.

In view at the 'tc-rcfmino' explanation of the manner in which a.substation A is controlled in ler lili crciit a r-cumstances it isbelieved that it will be unnecesear to enter into a detail descriptionof the ope ation oi the pay station equipment at substation A. Thesubstation A comprises an ordinary automatic telephone and a pay stationof well known type which is described in. the U. S. patent to Forsberg.Ito. 1,043,219, previously mentioned. The only change is in the circuitof the contact springs. which are so connected that the impulse springsof the calling device 5 are normally short circuited, from which it willappear that it will be necessary for the subscriber to deposit a coinbefore he can make a call. When calls are extended to local subscribersthe collection and rcfunding oi the deposited coins is controlled:uitomatically by the repeater D which applies either positive ornegative high potential to the line to actuate the polarized. magnet. atthe pay station to either collect or refund the coin, depending onwhether the call has been answered or not. The operation is identical sofar as the exchange :wparatus is concerned as it is in the case wherethe substation A is concerned. and 'a view oi" the tact that theoperation at a pay station oi this type when coins are being collectedor refunded is well understood, it is believed that further descriptionol the operation on automatic connections will be unnecessary.

ll hen long: distance connections are established with the aid of theoperator. deposited coins are oi course collected responsive to theactuation of the collect key by the operator which results also in theapplication of high voltage current ol? suitable polarity .to the line.In case it is desired to retund deposited coins it is not necessary forthe operator to take any action in order to accomplish this underordinary circumstances because when the calling subscriber hang-s up hisreceiver any coins which remain uncollected will be automaticallyrei'undcd by the operation oi the repeater D during the release oi theconnection. How ever. it may happen that the subscriber by mistake hasdeposited the wrong coins. In this case it will be desirable to refundthe coin without requiring the subscriber to hang up his receiver. witha view to his depositing the correct coin immediately thereafter. Toaccomplish this the operator will actuate hcr key marked lie't'uni'l.thereby energizing her relay Zlll. its a result. the high voltagebattery l3 and the lamp ll are substituted tor the uppe windcl relay 203d the exchange battery. operation is szn'iilar lo the operation lwhereby battery B w- 1 i cult and is iollmved by simi at the repeaterl). cxceptthat A e the current ti thru the bridged r a the 1=";)9i-.. iin the rcrerae direcy :3 lion, the electro-polarized relay till will notlit) oquiineiii as A uppci Gl. resting Contact o i? armaiiirc o1 gmaiirm resting Contact of arnia l li- "1 arinal'iire, and the worlcv' l: oarmafure (36 and rho contac A 4 i. sa' a fare to cowhx The current itrolline C(lllfll'lifi j V W tion (0 open 1 ay slai'ioii so a lVhci'l coinsor; 1 ed relay 61 is opcri: ml each 0'? course that coin l posited andthe polar oiincci'od jo the line, i'licroh niiori'nsd "hr-. ing isactually H I v hility of her being imposed upoi scribe]? Who mi -i',alilompt io ohii motion with-omit dsao vented. V 1

Having dcscrihcd my ilIFCBtlOD What I a conneci'ioir consider to be newand desire so have pro- Second liec-i'ed by Lotte. s Pricnt will bepoinied out 001111661 in the appended claims.

l i hat claim as my invention is:

couion to which coimcw liner 2 eifiPll callwl 1 connccl'io'a can only1):),

GIIiZGi d cal lm or 11c (21c (343 suing a (on; pio- 1. In a telephoneSfv'S 'C a :2 calling i: J l a and a line thercifoii' crztsndihg o i ing mower ,urroil: cs oppositc po excl!ange. charging cquipmcni, s 'iiy a:the citch swans at Mo c1;- i ioa inchfidiiig a polaritaso rolzi .7change operable i cull from said ho connected to rho liilc {or coil? s:iioii lo anioniai'icnllr connect on 1'" iihc l oi ihc llllm saidoperation of so:

liormallv res: in current iroin mar/i0 sWil'ch-os b i from said stationI M osho source and ii 2 cmonian'o to only to an OPQ'FZITOTE position aswherei th, one oz: said sources 5o 1;); the ac 'uaoperator may coinploictho connection to called station, currentsonrcos of opposiic polarityand moans whereby lhe operator Whilo main. aiming; the commotion canconii n of said mescr.

" i telephone svs;

iih an olsci'r ncct either of said sources to i118 calling oi? s2 hoe Tocontrol sasd iolay dosh-ml. a call is 2. lo a iOlPPl'HPlG systciii. acalling g ounded and a lino i hc ci' or cxiioi 'ng lo a ofichango foropor: exchang o ing cquipiiici ii at sand staisicr The (all and (ioniric ud oolarizccd ii och adapic rospoiisiro to il o Cori-mil lirol iiihas oncratcd.

the opcrai'ioo oi? said c. automai'io swrtc ig lrollahle from sauconneoiioii lo a or:

1 V 11 a lmeoh no a snlisialior r i i A sided with a motor. means i orairi'oiii:

li'a meeting said motor ,roro mind when (all is (.XCllElllQC 'i-orconnecting 'sristic jlll'lQiTi sources 5' 4'1 subscriber, (QTY-Chisoiirci-is or iarity, moans opsratcd zauiomzii' c the connection haheart or lo station to thorsa of said sources to rho c: 0pc *aiic saidchar ii the operation lliorm iior s. ozisivc iii cii'hor caso V V sireonly to a particular load of car; i

t ng; the: operation oi? sa'd ITIQiQL callii solifliccalled subscri iier.ii a tolcphoiio system, manual cqiiiprxient whcrohy a. coiiiioci'ioil'ltloll COlDPIlSlUg ia equipment call automatic s .i!'cl=os sender forstation,

, and a meter, the exchange controlled by said completing; conneczzoni'o called line iio l he o eraa second operaiioi' fended i said calliitors position may be completed io means for operating said meter whenthe callin subscriber hangs up his receiver, a. relay for preventing theoperation of said meter, and means for operating said relay when thecalling subscriber hangs up his receiver in case the called subscriberdid not answer.

8. In a telephone system, a substation pro vided with a meter forregistering calls, means for automatically connecting said meter to theline when a call is made, two current sources or" opposite polarity atthe exchange, n'ieans operable. after each call to connect one or theother oi said sources to the line, and a relay controlling said meterwhereby the said meter is permitted to respond to current from only oneof said sources.

9. In a telephone system, a substation provided with a meter forregistering calls, means for connecting said meter to the line when acall is made, two current sources of opposite polarity at the exchange,means operable after each call to connect one or the other of saidsources to the line, a relay controlling said meter whereby the saidmeter is permitted to respond to current from only one of said sources,and a second relay responsive to current from either of said sources todisconnect said meter.

10. In a telephone system, a substation provided with call registeringmechanism, current sources of opposite polarity at the exchange, meansfor connecting said mechanism to the line when a call is made, means atthe exchange operable after each call to connect one or the other ofsaid sources of opposite polarity to the line, said mechanism beingresponsive to current from only one of said sources, and meansresponsive to current from either of said sources to disconnect saidmechanism from the line.

11. In a telephone system, a substation and a line therefor extending toa central exchange, registering mechanism including a polarized relayconnected to the line when calling, a non-polarized electromagneticnictcr controlled by said relay, sources of current of opposite polarityat the exchange for controlling the operation and disconnection of saidmechanism, automatic switches con trollable by the subscriber at saidstation for extending a connection to a called line, and means wherebyone or the other of said sources is automatically connected to thecalling line after each connection.

12. In a telephone system, a substation and a line therefor extending toa central exchange, registering mechanism including a polarized relayconnected to the line when calling, sources of current of oppositepolarity at the exchange for controlling the operation and disconnectionof said mechanism, automatic switches controlled by the sub scriber atsaid station, an operators equipment cooperating therewith to extend aconnection to a called line, and means whereby the operator can connecteither of said sources to the calling line to control said registeringmechanism as desired.

l3. 111 a telephone system, a substation and a line therefor extendingto a central exchange, registering mechanism including a polarized relayconnected to the line when calling, sources of current of oppositepolarity at the exchange for controlling the operation and disconnectionof said mechanism, automatic switches controllable by the subscriber atsaid station for extending a connection to a called line, means wherebyone or the other of said sources is automatically connected to thecalling line after each connection, a magnet responsive to theconnection of either source to disconnect said mechanism from the line,and another magnet controlled by said relay and responsive to theconnection of a particular one of said sources to register a call beforethe mechanism is disconnected.

ll. In a telephone system, a substation and a line therefor extending toa central exchange, registering mechanism including a polarized relayconnected to the line when calling, sources of current of oppositepolarity at the exchange for controlling the operation and disconnectionof said mechanism, automatic switches controlled by the subscriber atsaid station, an operators equipment cooperating therewith-to extend aconnection to a called line, and means whereby the operator can connecteither of said sources to the calling line to control said registeringmechanism as desired, the connection of either source being effective todisconnect said mechanism from the line, and the connection of aparticular one of said sources being effective to register a call beforethe mechanism is disconnected.

15. In a telephone system, a substation and a line therefor extending toa central exchange, registering mechanism including apolarized relayconnected to the line when calling, sources ol current of oppositepolarity at the exchange lor controlling the operation and disconnectionof said mecha nism, automatic switches controlled by the subscriber atsaid station, an operators equipment cooperating therewith to extend aconnection to a called line, means whereby the operator can connecteither of said sources to the calling line to control said registeringmechanism as desired, the connection of either source being effective todisconnect said mechanism from the line, and the connection of aparticular one of said sources being efi'ective to register a callbefore the mechanism is disconnected, and subscriber controlled meansfor preventing the disconnection of said mechanism whereby it may be ope'ated a plurality of times] 16. In a telephone system, a subscribersstation, a registering mechanism connected to the line when calling,sources or current of opposite polarity at the exchange, means forconnecting one or the other of said sources to the line to control saidmechanism either before or after the receiver is replaced, and meansresponsive to either source only after the receiver has been replaced todisconnect said mechanism.

17. In a telephone system, a calling station and a line thereforextending to a central exchange, call registering equipment at saidstation including a polarized relay adapted to be connected to the linefor controlling the registering or extended calls, automatic switches atthe exchange controllable from said station lor extending connection toan operators position, means whereby the operator may complete theconnection to a called station, current sources of opposite polarity,means whereby the operator can connect either of said sources to thecalling line to control said relay as do sired, and a signal at theoperators position actuated during the control. of said relay when acall is being registered to notify the operator that the callregistering equipment is being operated.

18. In a telephone system, a subscribei"s station, registering mechanismat said sta tion for registering calls including a polarized controllingrelay, said mechanism being connected to the line when calling, automatic switches for extending the call to an operators position, sourcesof current of opposite polarity, means controlled by the operator forconnecting one or the other of said sources to the line to control saidregistering mechanism, and a signal for indicating to. the operatorwhether the said mechanism is connected or not.

19. In a telephone system, a substation having call charging equipment,current sources of opposite polarity at the exchange, means at theexchange operable after each call from said station to automaticallyconnect one or the other oi said sources to the line, said call chargingequipment being non mally responsive to current from either source, and.means responsive to current from only one of said sources for prm'entingthe assessing operation of said charging equipment.

20. In a telephone system, a substation and a line thereto!- extendinglo a central exchange, a toll assessing device including a polarizedrelay connected to the line when calling, sources of current of oppositepolarity at the exchange for controlling the operation and disconnectionof said device, automatic switches controllable by the subscriloer atsaid station for extending a connection to an operators position, meanscontrolled therefrom for extending a connection to a called line, andmeans at said operators position whereby one or the other of saidsources of current may be connected to the calling line at will.

21. In a telephone sys em, a subscribers station, registering mechanismat said. station for registering calls including a polarized controllingrelay, said mechanism being connected to the line when calling,automatic switches for extending the call to an operators position,sources of current of op posite polarity, means controlled by theoperator for connecting one or the other of said sources to the line tocontrol said registering mechanism, and a signal .ior indicating to theoperator whether the said mechanism is connected or not, said signal andreg-- istering mechanism operable any desired number of times whilemaintaining said connection.

22. In a telephone system, a subscribers station, automatic switchescontrolled by the subscriber at said station for extending a connectionto an operators switchboard or to another subscribers line, means atsaid switchboard for manually completing received calls to called lines,a call register at said station connected to the line when ever a callis made, means for automatically operating said register over the linecircuit to register automatic connections, or for op erating theregister under manual control to register manually completedconnections, and disconnecting means effective to disconnect saidregister from the line whenever it is operated automatically whilepermitting repeated. operation under manual control withoutdisconnection.

23. In a telephone system, a subscribers station, means at the exchangefor extending calls from said station to called lines, a call registerat said station connected to the line when a call is made, means forcontrolling said register over the line from the exchange to registercalls, and means effective only in case the receiver at said station hasbeen replaced for disconnecting said register from the line whenever thesame is operated.

M. The combination, with a substation meter, of means for connectingsaid meter to the line when a call is made, a circuit independent ol?the s\\'itchhool: :lor ruperating said meter over the line, a magnet.for dis connecting said meter lrom the line, and a circuit elfective foroperating said magnet only when the switchhook is in normal position.

25. The combination, with a substation meter, of means at the exchangefor transmitting currents of two different characters over the line, themeter being normally rcsponsive to current of either kind, and a relayassociated with said meter at the substation and responsive only tocurrent of one kind for preventing the response of the meter when suchcurrent is received.

26. The combination, with a substation meter, of means at the exchangefor transmitting currents of two different characters over the line, themeter being normally responsive to current of either kind, and a relayassociated with said meter at the substation and responsive only tocurrent of one kind for preventing the response of the meter when suchcurrent is received, said relay having contacts for shunting said meterto prevent its operation.

27. The combination, with a substation meter, of means at the exchangefor transmitting currents of two different characters over the line, themeter being normally responsive to current of either kind, and a relayassociated with said meter at the substation and responsive only tocurrent of one kind for preventing the response of the meter when suchcurrent is received, said relay being connected in series with saidmeter and having contacts effective to short circuit said meter whenclosed.

28. The combination, in an automatic substation equipment, of a meter, amagnet responsive to the actuation of the calling device for connectingthe meter to the line, locking means for maintaining the connectionindependent of said magnet, means for operating the meter over the linefrom the exchange, and an unlocking magnet also controlled over the linefrom the exchange for disconnecting the meter from the line.

29. The combination, in an automatic substation equipment, of a meternormally disconnected from the line, means responsive to the setting ofthe calling device for the first digit of a called number for connectingsaid meter to the line, and locking means for maintaining the connectionafter the calling device is restored.

Signed by me at Chicago, Illinois, this 8th day of December, 1919.

JOHN WICKS.

